The present invention relates to a cleaning method which is carried out in the process for producing a semiconductor device, a liquid crystal display or an electric element.
In producing, for example, a semiconductor device, particles such as organic or inorganic materials have been removed which adhere to a bare wafer or a wafer which is covered with an oxide film. Adhesion of the particles may result in generation of defects in the semiconductor device.
Thus, the particles have been hitherto removed by using a cleaning fluid comprising pure water (ultra pure water), or pure water (ultra pure water) from which dissolved air such as oxygen is removed. In the case of cleaning an object to be cleaned, for example, after rinsing the object with chemicals or a surfactant, the object is immersed into a cleaning tank and then the tank is overflowed with the cleaning fluid to clean the object, or the cleaning fluid is jetted out from nozzles to the object to clean the object. In particular, in the case of jetting out the cleaning fluid from the nozzles to the object to be cleaned, for the purpose of improvement on cleaning power and efficiency of removing particles the cleaning fluid is jetted out while thereto ultrasonic vibration is applied.
However, according to the aforementioned cleaning method, it is not necessarily possible to efficiently remove the particles adhering onto the surface of the portion to be cleaned, such as the surface of a bare wafer.